DOpamine is present in a special type of cell in sympathetic ganglia. The cells are known as small intensely fluorescent cells (SIF cells) because of their appearance after histochemical staining for catecholamines. These cells modulate information transfer from preganlionic neurons to postganglionic neurons. Our present objective was to evaluate the content of 3, 4-dihydroxy-phenylacetic acid (DOPAC) in the celiac ganglion as a biochemical indicator of SIF cell participation in ganglionic transmission.